What does "fully qualified" mean by itself and how it can be used?

I know this phrase from usage with DNS as Fully Qualified Domain Name but that's the only use case I'm aware of.

So, 1. I'm wondering what "Fully Qualified" means by itself and how it is applicable to other subjects.

and 2. is "fully qualified" and "unambiguous" interchangeable?

Solution 1:

Fully Qualified means that whatever it is has all the qualifications which are applicable. This could mean a qualification such as an FQDN has:

qualified adjective
2 not complete or absolute; limited

[ODO]

That is, a fully-qualified domain name is limited to a specific domain, and that limitation in scope is sufficiently stringent to make it unambiguous.

But they could be academic or vocational qualifications:

qualified adjective
1 officially recognized as being trained to perform a particular job; certified

[ODO]

In these cases one would not talk of an "unambiguous carpenter".

Solution 2:

Wiktionary: Qualification meaning 4 applies to the carpenter, while meaning 1 applies to the Domain Name. The Fully just means that there are no more qualifications required to make someone suitable for the work, or to remove ambiguity.